1. Field of the Invention
The present invention relates to a nodal point arrangement for keys on a keyboard in a notebook computer, and particular to an improvement of nodal point arrangement regarding keys on a keyboard used in a notebook computer.
2. Description of Related Art
A keyboard, which has been adopted for years, is a primary input tool for a computer in spite of many other available input devices. Because the keyboard is the simplest and easiest input periphery, it is not possible to be replaced completely by other input devices. Especially, the keyboard has been made a non-separable part in a notebook computer.
In fact, the actuation of a keyboard is by way of circuit nodal points under the keys. When a key is pressed, a nodal point corresponding to the key is touched to form a short circuit. Then, the software senses the short circuit to perform subsequent actions such as displaying on the screen, and driving programs in the computer to execute the command represented by the key.
It is conceivable that pressing a single key normally generates merely a signal and two signals will generate at two places in case of pressing double keys. As for the keyboard in a notebook computer, the specification thereof is a matrix of 16 columns and 8 rows as shown in FIG. 1 and that is there are 144 nodal points. FIG. 2 shows a prior art switch key layout in a keyboard. FIG. 3 shows the nodal points with respect to the keys shown in FIG. 2. As shown in FIG. 3, a key being pressed results in other 15 nodal points in the same row and other 7 nodal points in the same column being disconnected completely. In case of two keys being pressed at the same time, there are more nodal points are invalid accordingly. Therefore, all the keys on the keyboard in a notebook computer are not possible to keep active and the number of active keys are almost less than ninety actually. Comparing to a big keyboard for a typical personal computer, the keyboard on a notebook computer is less functional and this is a bottleneck has to be solved effectively.
Moreover, due to input commands being getting complicated, it is necessary to increase the required keys. But, the keyboard on a notebook computer has a limited space to provide an additional zone for functional keys such that it has been obliged to use a functional key (Fn) together with another key to input a command. In order to effect various input commands, it is necessary to use three keys together instead of two keys. However, it is not possible for the small keyboard provided in any notebook computer to perform the operation of pressing three keys together.
For instance, a PC 98 keyboard specification published by Microsoft Corporation has listed valid 3-key combinations in FIG. 4 and each valid 3-key combination includes two keys together with an ordinary key in a way of being pressed effectively. Each valid 3-key combination applied in a big keyboard is exactly three keys but four keys are required for the notebook computer. The fourth key required is the Fn key due to no specific zone for functional keys available. Therefore, it leads to a more difficult job to arrange nodal points of four key pressing in a notebook computer.
Indeed, the way for pressing a valid 3-key combination is required for the software usage. There are some key combinations for the software listed hereinafter as a reference.
Examples for the functions belonged to a operation system of Windows 9X are in the following:
Example for Microsoft Word application are in the following:
Example for Microsoft Excel application are in the following:
Example for ACDSee application are in the following:
In order to meet the operation requirements, a notebook computer supplier offers a 10xc3x9716 matrix instead of 8xc3x9716 matrix to increase the number of nodal points. However, this is a way resulting in substantial variations of the computer such as the software, the hardware, the mechanism, and the size such that a great deal of manpower and material have to be waste accordingly. In addition, the original molding tool and equipment have to be left unused completely. Therefore, an increased columns and rows for nodal points will cause a tremendous loss so that it is an unfavorable improvement if there is a possibility to have a better alternative under a condition of keeping 8xc3x9716 matrix unchanged.
An object of the present invention is to provide a nodal point arrangement for keys on a keyboard with which a combination of 3 keys or more can be obtained in a prior art nodal point layout of 8xc3x9716 matrix without increasing the dimension of the matrix size.